CLIMATEDOGS NATIONAL FORECAST

The main climate drivers are
continuing to not play a big role in influencing our climate at the moment,
however ‘Above Average’ temperatures in the eastern Indian Ocean are currently having
some impact. These warmer temperatures are helping to bring tropical moisture
across central and southern Australia, a pattern which looks likely to continue
over winter with several models indicating the potential development of a
negative Indian Ocean Dipole (IOD).

As a result, the overall outlook
for May to July is for ‘Above Average’ rainfall for most of the southern
two-thirds of Australia however, the Eastern Seaboard has no strong indication
of wetter or drier than average conditions. Both minimum and maximum
temperatures are likely to be ‘Above Average’ for most of Australia.

Rainfall Roundup

Above Average” and “Very Much Above Average” rainfall was recorded in
much of south eastern Australia; however Western Australia is still waiting for
the autumn break (Fig. 1). Nonetheless with these recent autumn rainfall events
in south east Australia there are still large areas that have serious rainfall
deficiencies which will require many months of ‘Above Average’ rainfall (Fig.
2).

Figure 1. Rainfall deciles for April 2020. Figure 2. Rainfall deciles for February to April 2020.

Rainfall Forecast

The BoM’s ACCESS model suggests that
May is likely to deliver ‘Average’ to ‘Above Average’ rainfall to much of
Australia (Fig. 3). For the three-month forecast, May to July, rainfall is
likely to be ‘Above Average’ for much of the southern two thirds of Australia however,
parts of the tropical north and eastern side of the Great Dividing Range have
roughly equal chances of being wetter or drier than average. Note that at this
time of year accuracy for the three-month forecast is moderate except for areas
in the south east of Australia, particularly South Australia, and areas in New
South Wales and Queensland where accuracy is low (Fig. 3).

Figure 3. Australian outlook for May to July 2020.

Temperature Roundup

Maximum temperatures in April were ‘Below Average’ in parts of south
eastern Australia but were ‘Above Average’ across northern and western
Australia (Fig. 4). These ‘Above Average’ temperatures broke many records in Western
Australia. For example, Perth recording its hottest April day on record (39.5°C)
and Mandora (SW of Broome) now holds the record for latest 42°C
day ever recorded (26th April).

Minimum temperatures on the other hand have been ‘Average to ‘Above
Average’ across most of Australia however a large part of Western Australia was
‘Very Much Above Average’ with small areas being the ‘Highest on Record’ (Fig. 5).

The BoM’s ACCESS model forecast
suggests that over the next three months maximum temperatures are likely to be ‘Above
Average’ across northern, eastern and the far southwest of Australia (Fig. 6). Minimum
temperatures are also likely to be ‘Above Average’ right across Australia for
the next three months (Fig. 7). At this time of year accuracy for the
three-month maximum temperature forecast is moderate to high for most of
Australia except for parts of the NSW coast and an area in the Northern Territory
and Queensland where accuracy is low. Accuracy for minimum temperatures is
moderate to high in northern Australia and Tasmania at this time of year
however the south western part of Western Australia and the south eastern states
have low accuracy.

Figure 6. May to July 2020 maximum temperature outlook.Figure 7. May to July 2020 minimum temperature outlook.

Climate and Water Outlook Videos

The Bureau of
Meteorology releases regular outlook videos, covering all this information.
Watch the most recent video below.